Income Taxes - Reconciliation of Statutory U.S. Federal Income Tax Rate to Company's Effective Income Tax Rate (Details)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
U.S. statutory tax rate	21.00%	35.00%	35.00%
Increase related to state and local taxes, net of U.S. income tax benefit	2.60%	(499.90%)	1.30%
Benefits and taxes related to foreign operations	(1.50%)	(2796.30%)	(6.20%)
Charge related to Global Intangible Low-Taxed Income	1.30%	0.00%	0.00%
RSU vesting and dividend discrete accounting charge or benefit	8.00%	(486.20%)	0.00%
Charge related to non-deductible compensation	1.80%	(38.70%)	0.40%
Rate change to deferred items related to Tax Cuts and Jobs Act	0.00%	(5193.70%)	0.00%
Other	(0.30%)	127.90%	0.40%
Effective income tax rate	32.90%	(8851.90%)	30.90%

Effective Income Tax Rate, from Continuing Operations, Before Noncontrolling Interests

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Effective Income Tax Rate Reconciliation, Change In Tax Rate Due To Global Intangible Low-Taxed Income, Percent

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Effective Income Tax Rate Reconciliation, Changes in Accounting Standards, Share-based Compensation, Percent

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Effective Income Tax Rate Reconciliation, Tax Cuts And Jobs Act Of 2017, Change in Rate of Deferred Tax Assets and Liabilities, Percent

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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